1. FIELD OF THE INVENTION
This invention is in the field of blast resistant framing structure and more particularly relates to a laminate or composite section for framing plate type panels.
2. PRIOR ART
Composite sections are known from Hartmam Profilkatalog 1986, in particular sheets 406 and 416. Between a pair of stay segments integral with respective lateral parts there is arranged a unitary strip of heat insulation material which embraces the end zones of the stay segment facing each other. Screws distributed at intervals over the length of the section pass through the lateral part from which they start and through the stay segment connected thereto, all the way, extending through bores disposed between the strips and into threaded bores in the opposite stay segment. In the known composite sections, fitted together substantially in double-T arrangement, one lateral part has a U-shaped cover section such that thereby a chamber is formed which extends over edge strips of the panels disposed on either side of the stay. Despite the screw heads positioned inside the chamber, a cavity remains in the chamber for accommodating therein reinforcements enclosed by the cover section and by the lateral part.
However, the known composite sections cannot be manufactured in a design sufficiently resistant to bombardment and explosive impacts. Under such stressed, pressure waves occur as a rule which stress the panels in alternating directions so that considerable tensile forces occur at the stay of the laminate section. The screw unions provided for holding the section parts together are insufficient for safe absorption of these forces. But even if the screws were strong engough to absorb the anticipated forces, there would be danger that a flange type lateral part would warp under the pressure of the panel and the panel would thereby lose its skirting frame. Therefore, the generally adopted arrangement of reinforcements in the chambers of such section combinations can, by itself, not help to improve the union of the section parts.
It is the object of the invention to provide a composite section for framing plate type panels wherein both a stable and sturdy union of the section parts under load in alternating or simultaneously in opposite directions as well as their deformationless force absorption is ensured.